1. Field of the Invention
The present invention relates to a shoe or boot provided with a heating device, particularly intended for downhill or cross-country skiing.
2. Description of Background Information
Ski shoes or boots are known which are intended to improve the comfort of the wearer by means of the incorporation of heating devices. These devices include the electric type, which use a heating resistance, and the liquid or gaseous fuel type, which use a reservoir of fuel and a burner positioned in the shoe or boot. The heating devices having liquid or gaseous fuel are advantageous, compared to electric devices, in making it possible to obtain a greater autonomy, making them more convenient, and to ensure, during a relatively long period of time, a desired level of comfort of the shoe or boot with regard to the temperature.
Heating devices using a liquid fuel, such as those described, for example, in Italian Patent No. 1,136,269 and French Patent No. 2,080,146, generally comprise a burner having rechargeable liquid fuel, which is positioned under a heat diffusion plate incorporated into the sole of the shoe or boot so as to extend as close as possible to the foot of the wearer of the shoe or boot. Other heating devices which use a gaseous fuel comprise a reservoir of gas which feed, through a valve, a catalytic burner, all of these elements being likewise totally positioned within the sole of the shoe or boot.
Such heating devices having gaseous fuel are described, for example, in Italian Design No. 196,850 and in International Patent Application WO 86/05663. Heating devices using gaseous fuel are of the type having a rechargeable gas reservoir and it is consequently necessary to provide, in the sole of the shoe or boot which contains the reservoir, an orifice through which the internal gas reservoir can be connected to an external recharging source of external gas.
The types of heating devices having liquid or gaseous fuel do have a disadvantage, however, in that the periodic filling of the fuel reservoir is required. This constitutes an inconvenient operation and particularly requires positioning near a combustible source to enable the recharging of the reservoir when the need arises Thus it is clear that the operation of filling the reservoir cannot be carried out easily and in certain circumstances can be very inconvenient and impractical, such as, for example, when the wearer is engaged in an outdoor sport, such as skiing, and he or she is in the middle of the mountain and the temperature is particularly low.